Onstage at TED, Nancy Kanwisher starts by telling us one of the most surprising results from recent neuroscience discoveries: The brain is not a general-purpose processor, but a collection of specialized components, “collectively building up who we are as human beings and thinkers.”

Imagine, she says, walking into a daycare center and suddenly realizing you can’t recognize any of the children, including your own. This isn’t a strange fantasy. It’s called prosopagnosia, and it happens to people. The really strange thing about it is, in those with that condition, only facial recognition is affected. There are many conditions like this, and Kanwisher say, “these syndromes collectively have suggested for a long time that the brain is divvied up into specific components.”

The effort to identify these components has jumped with the invention of fMRI, functional magnetic resonance imaging. Imaging has been around for a while, but the real advance happened when people discovered how to map activity. When neurons fire, they need more blood. And blood flow is local. So fMRI lets us see what parts of the brain are more active than others.

So, what can you learn from this?

One of her first studies was about face recognition. It was known that prosopagnosia affected a specific region, but was there something special about that region in healthy brains too? She went into a scanner herself, looking at images of faces and objects, for two hours straight. (“As someone who has close to the world record of total number of hours spent in a scanner, I can tell you one of the most important skills for fMRI research is bladder control.”)

The images were primitive by today’s standards, but she found a region with higher activity. Was it a fluke? To test that, she repeated the test many times, and then scanned other people. It turns out almost everyone has a similar face-processing region in a similar part of the brain.

“But what does this region actually do?” Is it really face-recognition? Or does it do other things? Maybe it responds to any body part, or anything human, or anything round. She spent a lot of the next few years testing those hypotheses.

Does that nail it? Nope. Brain imaging can’t tell you if the region is necessary for anything. “Brain imaging can only tell you what regions turn on and off. To tell what part of a brain is necessary for a function, you need to mess with it.”

They did get one chance with an epileptic man. As part of a diagnostic procedure, electrodes were implanted to find the source of his epilepsy, and by chance two electrodes were in the face region. With his consent, they asked him what happened when they stimulated the region. When they did, he reported their face changed — into somebody he’d seen before. “This experiment finally nails the case,” says Kanwisher. “This region is not only selectively involved in facial recognition but causally.”

There are many other specialized parts of the brain. Kanwisher spent a lot of time in the scanner in the past month to show them to the TED audience. She takes us on a visual tour, showing the locations of regions that respond to:

Faces.

Color.

Regions of space.

Visual motion.

Body parts.

Hearing sounds with pitch (As opposed to sounds w/o pitch).

Hearing sounds without pitch.

Speech.

Are there specialized regions for complex processes? She says yes, including regions for:

Language. A very specific part: understanding the meaning of a sentence.

When you’re understanding what another person is thinking, “the most amazing region we’ve found so far.”

There are probably more to be discovered. “But importantly,” she said, “I don’t think we have specializations in the brain for every important mental function.”

A few years ago a scientist in her lab thought he had found a special region for detecting food, which would be important for survival. But then he designed the crucial experiment to test that hypothesis. It turns out it wasn’t about food, but colors and shapes. Again, not every process has a specific place in the brain.

So, how do we process all the other information? “In addition to these highly specialized components, we also have a lot of general-purpose machinery.” They have found certain regions that seem to be engaged with any difficult task at all.

Kanwisher also points out that these regions are present in pretty much any normal brain in pretty much the same region — they are part of the fundamental machinery. It didn’t have to be this way: “The brain could have been more like a kitchen knife than a Swiss Army knife.” Instead we have a complex and rich picture of general-purpose components as well as highly specialized components.

It’s still very much the early days of this kind of work, she says: “The most fundamental questions remain unanswered.” For example:

What do these regions do?

Why do we need several face regions?

How do they divide tasks?

How are they connected?

How does this very systematic structure get built? In an individual’s development and through human evolution?

She closes by talking about the high cost of neuroscience research, and noting that many people justify it based on the promise of cures. Of course that’s important, she says, but, “This is worth doing even if it never led to treatment for another disease. What could be more thrilling than to understand the fundamental mechanisms that underly human experience, who we are? This is, I think, the greatest scientific quest of all time.”

TED2014, our 30th anniversary conference, is less than a month away! If you’re counting the days like we are, get a head start by reading some of the insightful and compelling books by the groundbreaking thinkers who will speak in Vancouver. Books from speakers in Session 1, “Liftoff” Being Digital, by Nicholas Negroponte. This 1995 […]

TED2014 is our 30th-anniversary conference, and the speaker lineup is — in a word — thrilling. Speakers will touch on topics ranging from technology, entertainment, design and education to climate change, architecture, music, physics, parenting, typography, fireflies and the Golden Gate Bridge. Randall Munroe of xkcd will talk about his passion for What If questions. […]

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In terms of the underlying mechanisms I have wondered many times what my brain looks like when I listen to Leonard Cohen’s music. (in particular, Take This Waltz) I have friends who say, “yea, it’s an O.K. song.”, but I feel an extreme overwhelming adoration for the song.. the words, his voice, the melody transports me to another place!
I wonder what my brain is doing that is not happening in the brains of those others. In fact I went to a Leonard Cohen concert and most of the people there appeared to be pretty much in another world. The Leonard world.
Is there any research into what makes us different when we see or look at art or hear a poem.
Is there an art area?
Do artist light up differently?
Why does Picasso draw some people while Rembrandt draws others?
Do we see the world differently in our brains? I’ll bet we do!
Thank you for prompting my brain to consider all these things. I wonder what part of my brain has been lighting up as I write this???

Yes … Areas of our Brains do ‘light up’ spontaneously in responding to a stimulus … but must do so, uniquely, hence, somewhat differently … Because, there’s no Standard Response, beyond the Locale of an individual’s Sensory Responsibilities …
But at times, when these experiences transcend Reason, these are called, ESP, or the Sixth Sense, in being there, but beyond our commonly shared experience, with Five Senses …

Thus, a Brain’s lit-up “area-graphs” representing an event, must vary from individual to individual … Because … of the difference, of each individual’s Share … as his or her unique Experience, of Reality !

“Arts” … Music, Poetry, Painting, Literature and a host of other such “Felt” human experiences, viz. love … are also Felt, in being “Closer” to one’s Sense, of Reality … it may, be shared by other, to an equal, a more, or a lesser degree …all depending on how, one “Sees” the other’s “Reality” …

That the Five “Senses Perceived” Feelings, are an Unique Personal experience, that varies from individual to individual … Thus, what Mozart “Felt” … considering the fact that he were Deaf at a point in life, and do correct me, if it were some other composer … nonetheless, Mozart’s Sense gets Shared, by “listening ears” of others, in yet other hands performed, philharmonic renditions, of his composed, Symphonies …

No fMRI’s can report this …

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In my ‘Belief’ … though many would gladly crucify me for using the term … there’s a world of difference, between a Silicon Microprocessor and a bio-electricity operated human organ called the brain …

Because, the Law, governing Silicone processors is … “What goes in, comes out” … whereas, the Brain is a complex “Tool” of the Mind, because, a lot more comes out than what our physical Senses feed it …

Thus, our differences, vis a vis, your deployed Prosopegnosia … as “something” that defines, what in my belief, is closer to, what you call Metaphysics, than a Complex or a Syndrome; that it’s Psychology’s ‘Compartmentalisation of the Brain, and treating its as the human Mind … has to do with it.

Let me say, the Tragedy of Science [and Technology] is of Sophoclean nature for Theory and Empiricism, reminds me of Oedipus … where each tiny step forward, is treated as the final … Giant Leap, Forward … and celebrated !

That I do not deny the fact that certain part of Brain do light up with certain physical activities … but I wish, Hub Pages had not ‘deleted’ my comments about this Mind-Brain difference and you could have read the deleted …

That invention of fMRI technology, is one such leap forward … it shows Electrical activity of brains, marked with certain electro magnetically recordable ‘flares’ treated as areas of ‘localised’ activity and the area, shown on a map and marked as the local epicentre, of a distinct brain … erroneously called, Mental activity !